It was 4am at 40,000 ft when most passengers were fast asleep on a seemingly peaceful flight when an elderly woman's heart suddenly stopped.
Mr Max Davidson was on board a 14-hour Singapore Airlines (SIA) flight from Singapore to London last month when his wife, Patricia, stopped breathing not once, but thrice.
But Mrs Davidson survived the ordeal, thanks to a group of helpful flight attendants and passengers.
Mr Davidson, who did not get to thank those who helped, wrote a contribution to the Daily Mail in tribute of the unsung heroes.
On a fateful Wednesday a month ago, Mr Davidson and his wife were returning home on the SIA flight.
Mrs Davidson had just returned to her seat from the restroom when she told her husband that she was not feeling well, so Mr Davidson pressed the call button to request for a glass of water.
After barely two sips, Mrs Davidson slumped onto her husband's shoulder and her eyes rolled upwards. Her breath was choppy, and then, she lost a pulse.
Desperate, Mr Davidson cried out for help, saying: "I need a doctor fast!"
Two stewards raced forward to assist Mr Davidson and pulled the woman out of her seat and onto her back in the aisle, while the stewardesses fetched oxygen cylinders and first aid kits.
Three passengers, who identified themselves as doctors, also came forward to help. They were also joined by a nurse.
One of the doctors, who was a cardiologist, began trying to resuscitate the woman.
As soon as the emergency was known to the captain of the flight, who then conveyed the situation to London's air traffic controllers, he was given permission to make an emergency landing at Heathrow Airport.
After Mrs Davidson came round, she was carried to the first class cabin to rest.
But her heart failed once more and the medical professionals on board performed CPR on her again.
The third time her heart stopped was when the plane was about to land. But the doctors risked their safety, unfastened their seatbelts and continued to revive her, according to Daily Mail.
As the plane landed 30 minutes ahead of its scheduled flying time, paramedics were stationed on the ground to receive the sick passenger.
In a flurry of being transported to the hospital, Mr Davidson did not get to thank those who helped save his wife's life.
Later, it was found that Mrs Davidson had a pulmonary embolus, which is a clot in the lung caused by the long flight.
She had to spend several days in the intensive care ward and a few more days in the cardiac care unit, reported the UK publication. She has since been discharged and is in good health.